Mold ejector device



Patented Nov. 10, 1925.

UNITED STATES PATENT OFFICE.

HERMAN RAU, OE: HAMILTON BEACH, AND CHARLES E. CHAPLE, OF BROOKLYN, NEW YORK, ASSIGNORS T DOEI-ILER 'DIE-CASTING CO., A CORPORATION OF NEW YORK.

MOLD EJECTOR DEVICE.

Application filed October 16, 1923.

To all fio/m it may Concern:

Be it known that we, HERMAN RAU and CHARLES lll. CHArrLE, citizens of the United States, and residents of Hamilton Beach, county of Queens, and State ofNew York, and Brooklyn, county of Kings, and State of New York, respectively, have inventet certain new and useful improvements in Mold Ejector Devices, of which the following is a full, clear, and exact description.

Thilo our invention is applicable to sand molds as used in foundries, it is of special utility in connection with the casting of molds of plastic composition, such as plaster of Paris, from match plates or patterns according to the process of the patent to John Kralund, No. 1,335,509 issued March 30, 1920, and will be described in connection with that process. That process consists in casting or otherwise forming a plurality of pattern units which are matched and assembled into one complete pattern called a match plate, and then with the aid of a flask or frame, as is usual with poured molds, flowing plaster of Paris upon the match plate, the plaster casting thus made being used as the mold for the finished casting. This process is of utility, for instance, in making castings from metals having relatively high melting points, such as brass, the mold being broken away or otherwise removed from the casting thus formed.

It will be appreciated that the lifting of these molds from the match plate or pattern is accompanied by a certain liability of injury to the mold, due to its fragile composition, either as a result of unsteadiness of the hands in manual lifting or friction between the various faces of the mold and its pattern. Since it is impossible to get underneath the mold to support it until after it has been lifted far enough away from the pattern or match plate, it frequently happens that the friet-ion between pattern and mold at deep pockets will cause the mold to collapse when it is ejected An object of our invention is to provide means for lifting the plaster mold and its flask with the required degree of steadiness and at the same time supporting the mold at such points as is necessary until the fingers can get underneath to support it at these points. Another object is to coordinate with mold and .flask lifting means,

serial No. 668,807.

other means for removing in advance of the mold any overhanging part of the patw tern or match plate which is used for casting an undercut in the mold in case the pattern has such a part.

In accordance with our invention we equip the match plate with loose ejector pins which are dropped into holes drilled in the plate and supported therein with their inner ends fiush with the surface oft-the pattern. Since these pins are independent of the ejector plate, it is possible quickly and cheaply to equip any match plate so that -its mold may be mechanically ejected, and

to arrange thel pins, for example at the bottom ot' deep pockets, so that the mold will be supported at the necessary points, while it is being ejected. Furthermore by adopting pins of the proper length a removable overhanging part of the pattern may be ejected in advance of the mold.

Our invention has other objects and advantages and includes other features of construction as will appear from the following description of one embodiment of our invention.

7e will now describe the illustrated enibodiment of our invention and will thereafter point out our invention in claims.

The drawing shows an elevation, partly in section, of one embodiment Vof our invention.

rlhe illustra-ted device has a base l upon which is a frame consisting of an annular,

plate 2 and supporting posts 3 between which move an ejector plate i toward and from the plate 2. rlhe ejector plate is elevated and lowered through one or more racks 5 operated by a pinion or pinions 6.

Supported on the frame 2 is a match plate or pattern 7. This pattern is the positive of the final casting, the plane portion of its face forming the parting line for the mold, and its raised portions forming the mold recesses. A flask or frame 8 rests upon the upper face of the pattern 7, and the plaster of Paris is flowed within this flask to form the mold 9.

In order to receive and support ejector pins 10, the pattern 7 has a plurality of holes drilled therethrough. In the form shown these holes are slightly enlarged in diameter at their upper ends, and the pins are provided with heads adapted to fit snugly in the enlarged portions of the holes and have their upper ends just flush with the surface of the pattern. As a general designation we refer to these holes as countersunk and to the pins as headed, and it will be understood that wedo not use these terms in any limited sense, but intend them to cover any equivalent construction vin which the holes and pins are so shaped that the pins are supported therein independently of the ejector plate.

The location `of the ejector pins will depend 4upon the contour of the pattern. Certain of them will be disposed underneath the flask S and the others will be properly disposed within the boundaries of the flask so as to lift the mold and support it at the proper points. In the construction shown these points are where the mold is the thickest, that is, where there are relatively deep pockets in the pattern, and generally speaking, those are the points that will be selected for the ejector pins.

In the construction shown the pattern includes an overhanging' part 7n for the purpose of casting an undercut in the mold 9. Obviously the mold cannot be ejected until the overhanging' part of the pattern has been removed. In the form shown the part 7 is supported in a hole in the pattern, rest-ing upon a shoulder provided for that purpose. The hole is continued through the pattern or match plate and an ejector pin 1l is disposed in this hole underneath the bottom of the part 7a and has its lower end resting upon the ejector plate 4L.

It will be understood that in assemblying the match plate and the other parts of the device, the match plate is attached to the .frame 2 by means of screws, clamps, or any other means of fastening. TheY relatively short ejector pins l0 may be dropped in the match plate either before or after it is secured on the frame 2. The ejector pin ll is then dropped through its hole in the match plate and the part 7 is set into the pattern. The flask 8 having then been placed upon the match plate, the mold may be poured. As the ejector plate 4 is raised, it is evident that the pin 11 will first eject the overhanging part 7a of the pattern and that the ejector a vpattern supported above the ejector plate and having a plurality of countersunk holes therethrough, and a yplurality of headed ejector pins supported by their heads in said countersunk holes in the pattern.

3. A mold ejector device comprising an ejector plate and operating means therefor, a pattern supported above the ejector plate having a plurality of countersunk holes therethrough and having' an upwardly removable overhanging part for casting and undercut supported in one of the said holes, a relatively long ejector pin in the hole underneath the said removable part of the pattern, and a plurality of shorter ejector pins provided with heads and supported by their heads in the countersunk holes.

et. A pattern having a plurality of countersunk holes therein, and a plurality of loose headed ejector pins supported by their heads in said countersunk holes.

5. A mold ejector device comprising an ejector plate and operating means therefor, a pattern supported above the ejector plate and having a plurality of countersunk holes therethrough, a flask resting `on the pattern over certain ofthe countersunk holes, and headed ejector pins supported by their heads in the countersunk holes underneath the flask and in certain of the other holes.

VIn witness whereof we hereunto subscribe our signatures.

HERMAN BAU. CHARLES E. GHAPPLE. 

